How to easily adjust multiple sum ranges without using date fields

I'm trying to build a daily production projection sheet, and I'd like to make a few aspects of it easier for the people who will be using the sheet throughout the year.

Sum Sample.xls

In the attachment, you will notice three hidden columns (J:L). For the sake of the example, let's assume that today is Monday, April 23rd. As each day passes, the previous day's column is hidden, and only the upcoming 15 days of data (including today) are visible to the eventual recipients of the projection form (the file is printed into a PDF generator when ready, so the page breaks restrict what makes it to the visible end product). I have my vertical formulas solved so that the entry user won't have to do anything to adjust them as the days, weeks, and months pass. The horizontal formulas will need to work differently, however.

I am concerned with columns F, G, and I. Column F sums everything from the start of the daily tally to the day before yesterday (in this case, Saturday, April 21) to show all of the confirmed production quantities. Column G does a single cell call to yesterday (in this case, Sunday, April 22) to show the unconfirmed, but projected production for the previous day. Column I looks at today through 15 total days forward (as mentioned earlier, including today) to provide a total of projected production over the next ~2 weeks. The simplest way of handling this is to have the entry user manually adjust the formulas for one row, then copy and paste them to the rest of the rows. Is there a command that can be used to extend F by one cell to the right, shift G by one cell to the right, and shift I by one cell to the right each day? If not, is there a way to write a formula that automatically handles it without having to use the date?

Thanks